Snapshots are an interesting feature of Btrfs. A snapshot is a copy of a subvolume. Taking a snapshot is immediate. However, taking a snapshot is not like performing a rsync or a cp, and a snapshot doesn’t occupy space as soon as it is created.
Editors note: From the BTRFS Wiki – A snapshot is simply a subvolume that shares its data (and metadata) with some other subvolume, using Btrfs’s COW capabilities.
Occupied space will increase alongside the data changes in the original subvolume or in the snapshot itself, if it is writeable. Added/modified files, and deleted files in the subvolume still reside in the snapshots. This is a convenient way to perform backups.
Using snapshots for backups
A snapshot resides on the same disk where the subvolume is located. You can browse it like a regular directory and recover a copy of a file as it was when the snapshot was performed. By the way, a snapshot on the same disk of the snapshotted subvolume is not an ideal backup strategy: if the hard disk broke, snapshots will be lost as well. An interesting feature of snapshots is the ability to send them to another location. The snapshot can be sent to an external hard drive or to a remote system via SSH (the destination filesystems need to be formatted as Btrfs as well). To do this, the commands btrfs send and btrfs receive are used.
Taking a snapshot
In order to use the send and the receive commands, it is important to create the snapshot as read-only, and snapshots are writeable by default.
The following command will take a snapshot of the /home subvolume. Note the -r flag for readonly.
Instead of day1, the snapshot name can be the current date, like home-$(date +%Y%m%d). Snapshots look like regular subdirectories. You can place them wherever you like. The directory /.snapshots could be a good choice to keep them neat and to avoid confusion.
Editors note: Snapshots will not take recursive snapshots of themselves. If you create a snapshot of a subvolume, every subvolume or snapshot that the subvolume contains is mapped to an empty directory of the same name inside the snapshot.
Backup using btrfs send
In this example the destination Btrfs volume in the USB drive is mounted as /run/media/user/mydisk/bk . The command to send the snapshot to the destination is:
This is called initial bootstrapping, and it corresponds to a full backup. This task will take some time, depending on the size of the /home directory. Obviously, subsequent incremental sends will take a shorter time.
Incremental backup
Another useful feature of snapshots is the ability to perform the send task in an incremental way. Let’s take another snapshot.
In order to perform the send task incrementally, you need to specify the previous snapshot as a base and this snapshot has to exist in the source and in the destination. Please note the -p option.
Once the operation is complete, you can keep the snapshot. But if you perform these operations on a daily basis, you could end up with a lot of them. This could lead to confusion and potentially a lot of used space on your disks. So it is a good advice to delete some snapshots if you think you don’t need them anymore.
Keep in mind that in order to perform an incremental send you need at least the last snapshot. This snapshot must be present in the source and in the destination.
Note: the day 3 snapshot was preserved in the source and in the destination. In this way, tomorrow (day 4), you can perform a new incremental btrfs send.
As some final advice, if the USB drive has a bunch of space, you could consider maintaining multiple snapshots in the destination, while in the source disk you would keep only the last one.
We recently interviewed Ankur Sinha on how he uses Fedora. This is part of a series on the Fedora Magazine. The series profiles Fedora users and how they use Fedora to get things done. Contact us on the feedback form to express your interest in becoming an interviewee.
Who is Ankur Sinha?
Ankur is a Computational Neuroscientist and has just started his first post-doctoral fellowship at University College London and a FLOSS enthusiast trying to spread the message of FOSS and evidence based science. Ankur started using Linux a decade ago, when he was introduced to Linux in a LUG doing an install fest during his undergraduate degree.
Ankur loves reading:
“I read a lot and tend to get attached to characters from books quite easily. Holmes, Poirot (I’m a detective fiction fan), Francisco D’Anconia (fan of the book Atlas Shrugged, but not so much Ayn Rand’s philosophy), lots of random characters from books I’d read. I also read lots of Hindi comics as a child—Doga, Super commando Dhruv, Naagraj, and Chacha Chaudhary—loved them all!”.
As far as all time favorite movies go, Swades comes to his mind. His favorite genre is science fiction thrillers (think “The Prestige” and ” Predestination”). When not busy working or engaging people on IRC channels, he enjoys listening to podcasts and classic rock.
Ankur’s favorite food is his mother’s Chhole Bhature. Otherwise, if he’s away from home, his go-tos are Butter chicken, Butter Naan, and Chilli Chicken from North Indian restaurants.
The Fedora Community
Ankur found about Fedora after a distro hopping phase in 2008, and since then he has been a fedora user. His first memory of the Fedora community is an IRC workshop on packaging fonts that the Fedora India community had organised back in 2008.
Talking to and meeting other community members has been one of the most exciting parts of the Fedora community for him. “I found this great bunch of people to hang out and geek out with! It was so much fun, and extremely educational both in terms of technical knowledge and the social/philosophical side of FOSS and life in general.”
When asked what he would change in the Fedora Project if he could change one thing, he said that he prefers “Smaller tweaks” since “Smaller tweaks also allow work to be spread out, and that really helps”. Specifically, he would like to see more discussion on the philosophy and nuances of FOSS in the community.
"Perhaps we all know it so well that we take it for granted and focus on the work that needs to be done. It’s so easy to get bogged down in the work, though, that I worry that we forget the bigger picture sometimes. The end for us is to promote FOSS, and everything we do is the means to this end. So, I worry that the means sometimes becomes the end for us — that we focus so
much on producing deliverables that we forget why we produce them."
Since he works in academia and science, Ankur would like the Fedora community (and FOSS in general) to get more involved with academic/scientific communities. “I think we have an excellent platform to enable education and research. NeuroFedora is a start in this direction.”
He wishes that other people knew that the Fedora community are not just OS developers, but a global community, and he’d like folks to just hang out and communicate even if they’re not contributing in the traditional sense of the word.
Ankur tries to help wherever he can, especially if newbies are involved. Nowadays, he tries to focus more on NeuroFedora as it fits well for his day-job and there’s so much to do in this Field + Open Science.
Ankur learnt most of the things from his >10 years of experience in Fedora and FOSS. He had learned theories of software development at undergrad but got to experience practical implementations from his colleagues in the community. He is a firm believer of “No question is a stupid question”. He adds that Fedora is perfect because it gets better as you start working with it.
His piece of advice for anyone thinking of getting involved in Fedora is to just go ahead and start. One doesn’t need to know anything at all. All of it can be learned over time. Secondly, don’t focus on tasks. Yes, that’s a good way of learning, but it is far more important to get to know the people of Fedora! As one meets more people, one learns more about how Fedora works and one has way more fun working and learning!!
Just like a lot of our community members, Ankur struggles from time constraints. His new challenge is to find more time to work on FOSS and Fedora. During his college years, it was to learn more and more.
One of the challenges Ankur faces about promoting open source is to explain to non-FOSS people that Windows/Mac aren’t the only OSes present. He thinks that having Fedora shipped with Lenovo systems will give a start for the community. It makes Fedora and FOSS more "official".
What Hardware?
Ankur has three machines and runs Fedora 32 on each of them:
Ankur’s Desk
Thinkpad E490 laptop
a custom workstation that university IT set up for research work
a headless MacPro5,1
2x Microsoft Sculpt Ergonomic keyboard/mouse/numpad
The PulseEffects app is a full-featured set of modular effects you can use to adjust sound devices. In a previous article, you learned how you can use PulseEffects to correct or enhance output devices like speakers. However, that’s not where its features stop. You can also enhance sound input devices such as microphones. This can help when recording sound for podcasts, videos, or the like.
This article assumes you’ve already installed PulseEffects as shown in the previous article. It will not cover advanced topics like recording musical instruments, but it will show you how to do better voice or spoken-word recordings.
A word on microphones
Microphones come in a variety of forms. The one almost every laptop user has at hand is the condenser microphone built into the hardware. These microphones are limited in terms of producing quality sound. They’re built to provide basic sound, and they will pick up a lot of environmental noise due to how they work. If you want better results for a voice recording, there are many choices available based on budget.
USB headset with built-in condenser microphone: Generally budget-friendly and almost always gives better results than a laptop’s built-in mic. The resulting sound can be somewhat harsh and tinny, but this can be corrected. Manufacturers such as Logitech make units that are plug-and-play ready for Linux. They show up as USB sound devices (both input and output).
Handheld dynamic microphone: You’ll see the singer in a live band using one of these. You have to be close to them (and maintain that distance steadily) for best results, but they sound full and well-defined. These are typically a little more expensive than a USB headset.
Large diaphragm condenser microphone: You’ll see this type used by a singer or speaker in a broadcast or recording studio. Like other condensers they pick up a lot of the surrounding environment. By being fairly close to the mic you can essentially “turn down” the rest of the room. You can find budget friendly, good quality large condensers starting at the same price as a good dynamic mic. Prices go up from there to astronomical levels!
Most dynamic and large diaphragm condenser mics need to be plugged into a digital audio interface, using a microphone cable. This converts the signal from the mic into digital audio for the computer to use. However, you can find specialty mics made for direct connection via USB. These may be advertised as “podcaster mics,” and you can save some money using one of these, versus buying both a mic and an interface.
Making the mic sound better
Effects help you improve the recorded sound of your microphone. Whether you know it or not, you hear these effects all the time in recorded sound — in music, in TV shows and movies, on professional podcasts, and via commercial and satellite radio. Engineers apply these effects using either hardware units, or via software.
PulseEffects provides these effects in a software form, before your recording is saved on disk. Here is a list, in the order they are usually applied:
A gate reduces or entirely mutes the microphone when sound falls below a certain level. With proper settings, when you start speaking, the gate quickly opens, unmuting the mic. When you finish, the gate closes and other environmental sound will be either silenced or much quieter.
A compressor reduces the dynamic range of the input. Louder sounds are caught by the compressor and squashed down. You then turn the entire signal up slightly to compensate. This way, quieter and louder sounds become closer in volume, making the sound more even and less “peaky.” This results in a more professional, polished sound that’s much more enjoyable for listeners.
An equalizer (EQ) tunes up the sound of the voice. Use it to mitigate tones in your voice that you find unflattering. In addition, when you speak close to a mic, the bass frequencies in the voice are unnaturally emphasized. Sound engineers call this the proximity effect. By using an EQ to roll off the low end frequencies, you can reduce this effect and create a more pleasant sound.
A limiter is often the last step in a signal chain. This effect puts an absolute limit on the volume of a sound, so that unexpectedly hard sounds (such as p or b sounds, called plosives) that aren’t caught by compression don’t distort and ruin your recording.
Dive into PulseEffects
Open up the PulseEffects app. In the top left corner, choose the microphone selector icon. This lets you set up the effects chain you want for the mic as an input device. As with output devices (speakers), you can save your effects chain as well.
Use recording software that registers as a PulseAudio client to see your effects at work. The PulseCaster app is one such app, but there are many others you can choose.
Tips from a mix engineer
These guidelines may help you find the optimal sound. Remember that no two sound situations are ever the same. Use your ears, and do some test recordings, to figure out what’s best for your situation.
When you apply the gate, use a fast response of 5-10ms. The human voice has a significant “startup time,” so this speed makes the gate unnoticeable. Give the gate some time to close, though, so you don’t cut off the end of speech. Typically 100-200ms sounds fairly natural. A gain reduction of -12 or -18dB suffices to reduce environmental noise, and sounds more natural than more extreme values.
If you find a module is overloading when you speak, either reduce the output of the effects module before it, or the input of the module itself.
If you like the sound of your recorded voice without an EQ, use the Filter module instead to simply apply a high pass filter. For male voices, use a roll-off frequency of 80-100 Hz. For female voices, use a higher value. If you set the filter too high, the recording may sound weak or nasal.
Use a compressor ratio between 3 and 4 (this is actually 3:1 – 4:1) which works well with a human voice. An attack of 20ms and a release of 100-200ms is typical.
You may want to try the Deesser module as well, to reduce the “sizzling” of s, z, t, and f sounds. Because voices vary so widely, you’ll need to tune this to taste. A split of 6kHz and a threshold of -18dB is a good place to start.
A limiter setting of -1 to -3dB usually works well. Much lower settings result in a very “squashed” sounding track. In some cases that may be useful; in others it will sound unnatural.
Refer to the previous article to save your effects chain. Remember, you can store multiple chains, and then select the one you want for your particular needs.
The Fedora Project is changing the default file system for desktop variants, including Fedora Workstation, Fedora KDE, and more, for the first time since Fedora 11. Btrfs will replace ext4 as the default filesystem in Fedora 33. The Change is code complete, and has been testable in Rawhide as the default file system since early July. The Fedora Workstation working group and QA team have organized a test week from Monday, Aug 31, 2020 through Monday, Sep 07, 2020. Refer to the wiki page for links to the test images you’ll need to participate. Read below for details.
How does a test week work?
A test week is an event where anyone can help make sure changes in Fedora work well in an upcoming release. Fedora community members often participate, and the public is welcome at these events. If you’ve never contributed before, this is a perfect way to get started.
To contribute, you only need to be able to do the following things:
Download test materials, which include some large files
Read and follow directions step by step
The wiki page for the kernel test day has a lot of good information on what and how to test. After you’ve done some testing, you can log your results in the test day web application. If you’re available on or around the day of the event, please do some testing and report your results.
Happy testing, and we hope to see you during the test week!
User data is the most important thing on a computer. Whether it’s source code for the next big release, family pictures, a music library, or anything else, you want it to be safe. Changing the default file system is not a change to make casually. The Fedora Project is changing the default file system for desktop variants (Fedora Workstation, Fedora KDE, etc), for the first time since Fedora 11. Btrfs will replace ext4 as the default filesystem in Fedora 33.
What does this mean for me?
Btrfs is a stable and mature file system with modern features: data integrity, optimizations for SSDs, compression, cheap writable snapshots, multiple device support, and more.
The switch to Btrfs will use a single-partition disk layout, and Btrfs’ built-in volume management. The previous default layout placed constraints on disk usage that can be a difficult adjustment for novice users. Btrfs solves this problem by avoiding it.
As a techie, you may have heard of bit rot, and memory bit flips. Data can be corrupted by a multitude of physical factors, even cosmic rays from the sun! Before an SSD fails outright, often it will return either zeros or garbage, instead of your data. Btrfs safeguards your data with checksums, and performs verification on every read. Corrupt data is never given to your programs, and it won’t replicate into your backups to be discovered another day (or year).
Btrfs uses a “copy-on-write” model: your data and the file system itself are never overwritten. This enhances crash-safeness. When copying a file, Btrfs does not write new data until you actually change the old data, saving space.
In fact, users will save more space when using Btrfs’ transparent compression. Compressing data reduces total writes, saves space, and extends flash drive life. In many cases, it can also improve performance. Compression can be enabled on an entire file system, or per subvolume, directory, and even per file. You will be able to opt-in to using compression in Fedora 33. And it’s one of the features we’re looking forward to taking advantage of by default in future Fedora releases.
Trusted
Facebook uses Btrfs on millions of machines in production. They compare its stability to ext4 and XFS (another file system available in Fedora). In fact, they use Btrfs to “improve” the quality of the consumer storage hardware that they use in production. Btrfs detects problems before the hardware fails.
(open)SUSE have been using Btrfs for many years now, including SUSE Linux Enterprise Server (SLES). You can’t imagine a company that provides support to customers shipping software that they don’t completely trust.
What’s next?
The Change is code complete, and has been testable in Rawhide as the default file system since early July. Btrfs has been explicitly supported in Fedora since 2012. This is expected to be a transparent change for most users, however it is still significant. Fedora will ensure we deliver the dependable and reliable experience Fedora users have come to expect.
Special thanks to: Ben Cotton, Michael Catanzaro, and the Fedora Workstation Working Group for contributing to this article.
Using Fedora and Linux to produce and play music is now easy. Not that long ago, it was a nightmare: configuration was a complicated task and you needed to compile some applications yourself. The compatibility with electronic devices was the real story. But, now we can see the end of the road. Playing music under Linux with Fedora is becoming user friendly.
Configuration
Fedora has long been usable to play music because of the CCRMA repository. Moreover, there also exists a Fedora Spin dedicated version: Fedora Jam. And today, you also have a COPR repository (which I manage) with a lot of stuff in it.
There are still some minimal steps to follow before being able to efficiently use a musical application. First, you will need to install the Jack audio connection kit and the qjackctl user interface:
dnf install jack-audio-connection-kit qjackctl
Then, as a root user, you will need to add yourself to the jackuser group:
sudo usermod -a -G jackuser <my_user_id>
To enable the changes made, you just have to logout of and log back in to your session or if you prefer reboot your machine.
Using basic applications
Now, you can add some applications to play with like LMMS or MuseScore.
All of these applications are available in the main Fedora repository:
dnf install lmms mscore audacity
Fedora and your instrument, in real time
Configuration
Editors note: A real time Kernel is necessary for audio recording on your PC, especially when doing multi track recording.
If you want to use your instrument (like an electric guitar) and use the sound of your instrument in some Fedora application, you will need to use Jack Audio Connection Kit with a real time kernel.
With the CCRMA repository, to install the real time kernel, use the following command as a root user:
dnf install kernel-rt
With the LinuxMAO Fedora COPR repository, use the following command:
dnf install kernel-rt-mao
The RT Kernel from CCRMA repository corresponds to a vanilla RT kernel with some Fedora patches applied whereas the one from the LinuxMAO repository is a pure vanilla one (a clean RT kernel without any patches).
Once this is done, we still need to perform some tuning on qjackctl to reduce the audio latency so it is negligible.
The main QJackCtl interface.
Click on the “Setup” button and set the following values:
Sample rate: 48000 or 44100 (this is the sampling frequency and these values are mostly supported on all commercially available sound cards)
Frames / period: 256
Periods / Buffer: 2
MIDI driver: seq (this value is required is you want to use a MIDI device)
With these parameters, you can easily achieve an audio latency of around 10 ms. While this value is the limit for the human ear and is hardly noticeable, you can reach lower latency with the penalty of increased CPU load.
Using Guitarix
To add some effects to your instrument, we will use a rack of effects: guitarix (edit: guitarix, the virtual guitar amplifier).
dnf install guitarix
Now, you have to connect your instrument to the audio card (the internal one or a USB adapter). Editors note: This normally requires an interface between the electric guitar and the audio line in of the audio card. There are also guitar to USB adapters. Once your instrument is connected, with qjackctl, we will connect:
the audio input to guitarix
the guitarix mono rack to the guitarix stereo rack
the guitarix stereo rack to the stereo audio output of your audio card
Connecting Guitarix using the QJackCtl graph window.
You do that by clicking on the Graph button of QJackCtl. Inside the Graph window, you just have to connect wires to the various elements . Each block represents an application. Guitarix is split into two blocks (preamp and rack). The preamp is where you select the amplifier characteristics, and the rack is where you apply mono and stereo effects. There are two other blocks with the system label for the audio input (the one on the left in the above figure) and the audio outputs (the one on the right).
Your instrument should be connected to the first audio input. You should test that your guitar is connected and that it’s able to be heard when played. Most of the time, we use the first two slots of audio output. But this will depend on your audio card.
Editors note: The actual configuration of inputs and outputs depends upon the type of hardware chosen. The stereo speakers of the PC were chosen as the output in the example shown.
If the MIDI interface of the sound card is chosen, there are also two red blocks which are dedicated to MIDI inputs / outputs. These would then be setup as the input from the instrument and the output from the rack.
Guitarix is an amp plus a rack of effects for you instrument. Mostly dedicated to guitar, but you can uses it with synthesizers too.
The Guitarix rack effects.
Adding some backing tracks
Better than just playing guitar on your own, you can play guitar with a group. To do this, we will install TuxGuitar.
dnf install tuxguitar
The TuxGuitar main interface.
TuxGuitar will play GuitarPro files. These files contains several instruments scores and can be played in real time. You just have to download a GuitarPro file from this website and open it with TuxGuitar.
Start TuxGuitar and click on Tools -> Plugins and check the fluidsynth plugin. Then, once fluidsynth is checked, click on Configure. Click on the Audio tab and select Jack as Audio Driver. In the Synthetizer tab, choose the same sampling frequency you chose for QjackCtl above (48000 or 44100 Hz).
In the soundfonts tab, you can add your own SF2 or SF3 file to improve the audio rendering. You can now close the Plugins window. Click on Tools -> Settings -> Sound. Here, you can select the king of audio used to render the score. If you have several SF2 / SF3 files, you will select the chosen one for the audio rendering here. Restart TuxGuitar after you’re satisfied with your selections. After restarting TuxGuitar, a new block will appear in the Graph window of QJackCtl.
QJackCtl with Guitarix and TuxGuitar.
You will just have to connect the block tagged ‘fluidsynth’ to the audio output like you have done with Guitarix.
Using MIDI devices
Using MIDI devices in real time is as easy as with audio. We will connect a virtual MIDI keyboard: vkeybd (but the same procedure applies with a real MIDI device) to a MIDI synthetizer: amsynth.
dnf install amsynth vkeybd
The main interface of AmSynth.
The virtual MIDI keyboard VKeyBD.
Once you have started amsynth and vkeybd, you will see new connections on the QJackCtl’s Graph window.
Amsynth and VKeyBD in QJackCtl’s graph window.
In this window, the red slots correspond to the Jack Audio MIDI connections whereas the purple ones correspond to the ALSA MIDI connections. Jack MIDI connections talk only to Jack MIDI connections. And the same for ALSA. If you want to connect a Jack MIDI connection to an ALSA MIDI connection, you will need to use a MIDI gateway: a2jmidid. You can read some more informations in the Ardour manual.
We have now covered some main topics of the audio under Fedora Linux. But there are a lot more things you can do.
Use some block connected language to perform many things: PureData
An audio / video block language: PureData
There is also a great audio looper available: SooperLooper.
SooperLooper, a great tool to build audio loops.
You can do live rehearsal through the internet: Jamulus.
Against the COVID side effects: Jamulus for live internet rehearsal.
Want to become the new famous DJ: have a look at Mixxx
Mixxx for DJing.
Webography
Some links now:
Here is a YouTube video where I play guitar through Guitarix and I use TuxGuitar to play the backing tracks in real time. Both TuxGuitar and Guitarix are sent through non-mixer which is a small mixing application. To be able to record the audio of the session “on the fly”, I also use timemachine. And to avoid reconnecting everything each time I want to play guitar, I use Ray Session to start every application and connect all the Jack Audio connections.
I also made a small demonstration of the use of Jamulus for a live rehearsal. On this YouTube video, I use Jamulus, QJackCtl, Guitarix mainly. The second guitarix is 30 km away. The latency was around 15 ms. It’s quite small and hardly noticable.
On this YouTube video, I tried to make some comparison between various SF2 / SF3 soundfont files. I used a GuitarPro file for the Opeth’s song “epilogue”.
On this YouTube video, I use MuseScore to play a GuitarPro file and I play along while my guitar sound is processed by Guitarix.
Here, it’s a live performance with a dancer. TuxGuitar + Non Session Manager + Non Mixer + Guitarix. I always used this kind of combination and Linux has never hanged … Finger crossed !
Some compositions made with LMMS on Fedora 25 to 32. Using some really nice plugins like Surge, NoiseMaker from DISTRHO package and others. All these compositions are libre music and are hosted on Jamendo.
If you need some help:
LinuxMusicians: a great place with skilled people willing to help
LinuxMAO: if you speak french, this is the place to be. A lot of resources related to various software.
LinuxAudio: another great website with various ressources to help.
Fedora test days are events where anyone can help make sure changes in Fedora work well in an upcoming release. Fedora community members often participate, and the public is welcome at these events. If you’ve never contributed to Fedora before, this is a perfect way to get started.
There are two upcoming test days in the upcoming week. The first, starts on Monday 17 August through Monday 24 August, is to test the Kernel 5.8. Wednesday August 19, the test day is focusing on testing GNOME. Come and test with us to make the upcoming Fedora 33 even better. Read more below on how to do it.
Kernel test week
The kernel team is working on final integration for kernel 5.8. This version was just recently released and will arrive soon in Fedora. As a result, the Fedora kernel and QA teams have organized a test week for Monday, August 17 through Monday, August 24. Refer to the wiki page for links to the test images you’ll need to participate. This document clearly outlines the steps.
GNOME test day
GNOME is the default desktop environment for Fedora Workstation and thus for many Fedora users. As a part of the planned change the GNOME megaupdate will land on Fedora which then will be shipped with Fedora 33. To ensure that everything works fine The Workstation WG and QA team will have this test day for on Wednesday, August 19. Refer to the wiki page for links and resources to test the GNOME test day.
How do test days work?
A test day is an event where anyone can help make sure changes in Fedora work well in an upcoming release. Fedora community members often participate, and the public is welcome at these events. If you’ve never contributed before, this is a perfect way to get started.
To contribute, you only need to be able to download test materials (which include some large files) and then read and follow directions step by step.
Detailed information about both test days are on the wiki pages above. If you’re available on or around the days of the events, please do some testing and report your results.
Unlike MusicXML, which is designed for exchanging music between score editing and performance applications, ABC is designed to be directly edited by humans. I can type a score in ABC with vim much faster than by fiddling with a mouse in a GUI score editor. Unlike other formats ABC works well with version control such as git. As with Latex, what you see is not what you get. But the notation is intuitive, the learning curve is pretty short, and the benefits are awesome.
While often touted as the standard for folk music, it works perfectly for Jazz lead sheets and does full scores as well. Some GUI score editors can import/export ABC notation. I used noteedit for a GUI editor until it was abandoned upstream, but was able to export as ABC. The result is reasonably human readable – letting me continue to edit in ABC notation, and serving as an example of a more complete score. When you are done with this lesson, you’ll be able to turn it into a PDF!
Ancient 4th Century Hymn
For a folk tune example, we will do a simple arrangement of a 4th century hymn, with a medieval era tune. “O Lux Beata Trinitas” is one of the twelve hymns which the Benedictine editors regarded as undoubtedly the work of St. Ambrose. It is cited as by St. Ambrose by Hinemar of Rheims in his treatise De unâ et non trinâ Deitate, 857. Hymnary.org
The hymn was still popular in the Gregorian Chant era. Here you can see the medieval notation and hear a performance as historically accurate as you will find today.
20th Century Interpretations
The medieval notation was updated in hymnals to more modern notation, This is our starting point. As reflected in those hymnals, there were no measures or bar lines in the medieval period.
Here are the basics of ABC:
Comments are lines beginning with ‘%’.
Notes beginning with “middle C” are entered as CDEFGABcdefgab.
Following a note with a number multiplies the timevalue by that number.
Notes that are next to each other are joined together whenever possible. This is the only way spaces are significant.
Parenthesis are used to tie or slur notes together.
The tune begins with X: 1, where 1 is the tune number. There can be multiple tunes in a file. Folk tunes are often collected into a file. For instance, we could collect all 12 known works of St. Ambrose into a single file named ‘ambrose.abc’.
The title is given with T:
The composer or source is given with C:
The key (default is C major) is given with K:
Here is a simple transcription of our tune into ABC:
X: 1
T: O lux beata Trinitas
C: Plainsong, Mode VIII
K: D
% Fedora Magazine example
(AB) (AGFG) EFG (AB) (BA) A4 (AB) (AGFG) EFG (AB) (BA) A4 (AB) d (cd) B (AG) (AB) (AGF) F4 (GA) (AGFG) EFG (AB) (BA) A4
We are going to do our work in a terminal emulator. Enter the above with your favorite text editor (bonus points if that is cat) into a file named ‘lux.abc’. Or download lux.abc with all the tunes for this lesson. To format and view this, we need ghostscript, xreader, and abcm2ps. You probably have ghostscript and xreader (or other PDF viewer) already installed on a desktop, but it doesn’t hurt to ask again.
$ sudo dnf install ghostscript xreader abcm2ps make
I had you install make so a simple makefile can simplify rendering:
Enter or download that as a file named ‘Makefile’. Now format and view our tune:
$ make lux.pdf
$ xreader lux.pdf &
I had you run xreader in the background, so you can switch back to your terminal. Xreader will update the view whenever lux.pdf is updated. If you are just reading this article, you can also view the output here.
Adding Lyrics
Lyrics are entered with ‘w:’ under the tune line they go with. Words are hyphenated to show how the syllables go with the notes. Use ’*’ to use additional notes for the last syllable.
Append tune 2 to the lux.abc file, it is the same tune with lyrics:
X: 2
T: O lux beata Trinitas
C: Words: St. Ambrose 4th century
C: Plainsong, Mode VIII
K: D
% Fedora Magazine example
(AB) (AGFG) EFG (AB) (BA) A4 w: O* lux*** be-a-ta trin-* ni-* tas, (AB) (AGFG) EFG (AB) (BA) A4 w: et* prin-*** ci-pa-lis U-* ni-* tas,
(AB) d (cd) B (AG) (AB) (AGF) F4 w: i-* am sol* re-ce-* dit* i-*gne-us, (GA) (AGFG) EFG (AB) (BA) A4
w: in-* fun-*** de lu-men cor-*di-* bus.
Now ‘make lux.pdf’ and see the results in your xreader window. Both tunes are rendered to the PDF.
Adding Measures
So, historical authenticity is all very fine, but I want to make a modern version. The first step for modern ears is to divide the tune into equal sized measures. My ear says that 7/8 is an excellent time signature for this tune.
M: 7/8
specifies a default meter of 7/8
L: 1/8
specifies a default note length of 1/8 of a whole note. This was already the default, but now it is documented.
Q: 1/4=80
specifies a suggested speed: 80 quarter notes per minute.
Measures are separated by bar lines represented by ‘|’.
There will be multiple verses, so ‘:|’ adds a repeat bar line.
A final bar line is ‘||’, but we don’t use it for this example.
It is good practice for debugging to divide the lyrics into measures as well, and not rely on automatic distribution.
Note that additional spaces can be added for readability.
Lining up the bar lines is not required, but can make it more readable.
Here is tune 3 with bar lines (appended to lux.abc):
X: 3
T: O lux beata Trinitas (3)
C: Words: St. Ambrose 4th century
C: Plainsong, Mode VIII
M: 7/8
L: 1/8
Q: 1/4=80
K: D
% Fedora Magazine example
z(AB) (AGFG) | EFG (AB) (BA) | A3-A4 |
w: O* lux***|be-a-ta trin-* ni-*| tas, |
z(AB) (AGFG) | EFG (AB) (BA)| A3-A4 |
w: et* prin-***|ci-pa-lis U-* ni-*| tas, | (AB) d (cd) B (A |G) (AB) (AGF) F-| F7|
w:i-* am sol* re-ce-|* dit* i-*gne-us,| * |
z(GA) (AGFG) | EFG (AB) (BA) | A3-A4 :|
w:in-* fun-***| de lu-men cor-*di-*|bus. |
Bass Line, Chords, and Verses
Now we begin the real departure in our interpretation. First, chords are added to assist in improvising from a “lead sheet”. Then we add a suggested bass line.
V:1
and
V:2
switch between voices.
Chords are entered in double quotes in the tune line, and are rendered above the following note.
Each comma after a note lowers it by an octave.
C:
can also be used to document arranger and license.
Addition verses are added as additional lyric lines under a tune line.
Verse numbers can be added by using ‘~’ to join them to the next word with a non-break space. Otherwise they would be counted as words.
%%MIDI
these are magic comments that are used in the next section!
Rendering that makes a nice lead sheet! What does it sound like? You will need the abc to MIDI translator and a MIDI renderer. Fedora comes with a number of MIDI synthesizer and rendering options, but we will use timidity – a simple command line utility that can render to audio files or play on your speakers.
Install abcMIDI and timidity:
$ sudo dnf install abcMIDI timidity++
If you have been following the examples, you have 4 tunes in lux.abc. Render them to midi with the abc2midi utility:
$ abc2midi lux.abc
This creates four midi files, one for each tune: lux1.mid .. lux4.mid. Use timidity to play each file to your speakers:
$ timidity lux1.mid
When you play ‘lux4.mid’, you will hear what the ‘%%MIDI’ directives did. You can read more about abc2midi and its directives here. You can also hear me singing and playing piano from the lead sheet and totally butchering the Latin.
There is a lot more to ABC, but this has hopefully been a fun introduction! There are more examples in /usr/share/doc/abcm2ps/examples, and check out folk tunes from many cultures.
Pipenv is a tool that helps Python developers maintain isolated virtual environments with specifacally defined set of dependencies to achieve reproducible development and deployment environments. It is similar to tools for different programming languages, such as bundler, composer, npm, cargo, yarn, etc.
A new version of pipenv, 2020.6.2, has been recently released. It is now available in Fedora 33 and rawhide. For older Fedoras, the maintainers decided to package it in COPR to be tested first. So come try it out, before they push it into stable Fedora versions. The new version doesn’t bring any fancy new features, but after two years of development it fixes a lot of problems and does many things differently under the hood. What worked for you previously should continue to work, but might behave slightly differently.
How to get it
If you are already running Fedora 33 or rawhide, run $ sudo dnf upgrade pipenv or $ sudo dnf install pipenv and you’ll get the new version.
On Fedora 31 or Fedora 32, you’ll need to use a copr repository until such time comes that the tested package will be updated in the official place. To enable the repository, run:
$ sudo dnf copr enable @python/pipenv
Then to upgrade pipenv to the new version, run:
$ sudo dnf upgrade pipenv
Or, if you haven’t installed it yet, install it via:
$ sudo dnf install pipenv
In case you ever need to roll back to the officially maintained version, you can run:
COPR is not officially supported by Fedora infrastructure. Use packages at your own risk.
How to use it
If you already have projects managed by the older version of pipenv, you should be able to use the new version in its place without issues. Let us know if something breaks.
If you are not yet familiar with pipenv or want to start a new project, here is a quick guide:
Create a working directory:
$ mkdir new-project && cd new-project
Initialize pipenv with Python 3:
$ pipenv --three
Install the packages you want, e.g.:
$ pipenv install six
Generate a Pipfile.lock file:
$ pipenv lock
Now you can commit the created Pipfile and Pipfile.lock files into your version control system (e.g. git) and others can use this command in the cloned repository to get the same environment:
If you encounter any problems with the new pipenv version, please report any issues in Fedora’s Bugzilla. The maintainers of the pipenv package in official Fedora repositories and in the copr repository are the same. Please indicate in the text that the report is regarding this new version.
To a veteran user of other distributions, Fedora can be a challenge. Many things are not where you expect them to be. The default LVM volume allocations are a bit tricky. And packages including the kernel are frequently upgraded. So why switch after years of using other distributions?
In my case, for a variety of technical and political reasons, Fedora was the best option if I wanted to continue using Linux as my daily driver. If you are making the transition from another distribution, here are some observations and tips to get you started.
Firm foundations
In Fedora you will find a community just as fiercely dedicated to its users and free software as Debian, as fanatical about polish and design as anyone in Ubuntu, and as passionate about learning and discovery as users of Arch or Slackware. Flowing under it all you will find a welcoming community dedicated to technical excellence. The form may change, but underneath all the trappings of systemd, dnf, rpm, and other differences, you will find a thriving healthy and growing community of people who have gathered together to make something awesome. Welcome to Fedora, and I hope you stay awhile.
The best way to get to know the Fedora community is to explore it for yourself. I hope a future article will highlight some of the more interesting aspects of Fedora for newcomers. Below are a few tips that I have put together to help you find your way around a new Fedora installation.
Install and explore
Installation proceeds as you would expect but be aware that you might want to adjust the LVM volume allocations in the install process or shortly afterwards or you might run low on space in a key place unexpectedly! Btrfs is also a supported option that is worth a look if you have lots of small disks.
Freedom matters
As stated above Fedora has a software freedom commitment similar in spirit to that of Debian. This means that you should be able to give Fedora to anyone, anywhere without violating intellectual property laws. Any software which is either not licensed in a way that Fedora finds acceptable or that bares US patent encumbrances can be found in the rpmfusion.org repository.
After the install your next concern is undoubtedly configuring things and installing new packages. Fedora’s command-line package manager is dnf. It works as you would expect.
Note also that since rpm uses file-based dependency tracking instead of package-based dependency tracking, as almost all others do, there are very few traditional metapackages. There are, however, package groups. To get a list of package groups, the command is:
$ dnf group list
To get a list of all installed packages on the system, the command is:
$ rpm -qa
All rpm commands are easily filterable using traditional Unix tools. So you should have no trouble adapting your workflow to the new environment. All the information gathered with the below commands can also be gathered through the dnf command. For information gathering, I prefer to use the rpm command because it presents information in a way that is easily parseable by commands like grep. But if you are making changes to the system, it is easier and safer to use dnf.
To get a package’s version, description, and other metainformation the command is:
$ rpm -qi <packagename>
To list the contents of an installed package the command is:
$ rpm -ql <packagename>
One way in which rpm is easier to use then dpkg or the slack package tools is that rpm stores change log information for each package in the package manager database itself so it is very easy to diagnose whether an update might have broken or changed something unexpectedly. This command is:
$ rpm -q --changes <packagname>
On the kernel
Perhaps one of the most exciting differences between Fedora and other projects, for newcomers at least, is Fedora’s policy on the kernel. Fedora’s policy is to align the distribution’s kernel package life cycle with the upstream mainline kernel life cycle. This means that every Fedora release will have multiple major kernel versions during its lifetime.
This offers several advantages for both users and developers. Primarily, Fedora users are among the first to receive all of the latest drivers, security fixes, new features, etc.
If you do not have an installation that uses out-of-tree modules or custom patches this should not be much of concern to you. However, if you rely on a kernel module like zfs, for example. Rebuilding the filesystem module every 2-3 months can get tedious and error prone after a while. This problem only compounds if you depend upon custom patches for your system to work correctly. There is good news and bad news on this issue.
The bad news is, as with all things kernel related in all projects, going the custom route means you’re on your own in terms of support. The 2-3 month lifecycle means you’ll be building modules and kernels far more often then you are used to. This may be a deal breaker for some. But even this offers an advantage to the discerning or adventuress user. You will find that being encouraged to rebase your custom kernel setup every two to three months will give you far greater insight into what is going on upstream in mainline Linux and the various out of tree projects you rely on.
Conclusion
Hopefully these tips will get you started exploring and configuring your new Fedora system. Once you have done that. I urge you to explore the community. Like any other free software product of Fedora’s age and size, there are a plethora of communication channels available. You should read the code of conduct and then head over to the communication page on the wiki to get started. As with the distribution itself, for all the differences in culture you will find that much remains the same.
